Cajon Plan

The construction is quite simple, but requires a care in making it square and sealing every joint well

Cajon Overview

This gives a good overview of the cajon. Its made of three grades of Baltic birch. The sides are 1/2". The "skin" is 1/8" and the side opposite the skin is 1/4". The sound hole is approximately 4" diameter. The drum is virtually air tight with reinforcing cleats in each of the inside corners. It has a nice deep bass sound when struck in the center of the skin and a sharp higher pitch when struck on the edges.

How the cajon is played

Greg demonstrates the classic position for playing the drum. The musician is truly in touch and "one" with his instrument. Bare feet add to the overall experience.

Wood finish

The cajon sides are dyed with a turquoise blue water based dye (Homestead Transfast dye powder #123831). The skin and sound board are unstained. The entire drum is finished with 4 coats of shellac and 4 coats of nitrocellulose laquer. Final finishing included rubbing with 800 grit paper lubed by mineral spirits, #0000 steel wool, and automotive compound. Paste wax is the final finish coat.

Cajon parts

Here's the original sides after all final cuts are complete.

Cajon sound hole

We used a circle cutter on the drill press to make the inital hole. The sides of the hole were shaped using a round-over bit in the router. The bit depth was originally too deep and so we had to use rasps and files to clean up the edges of the hole by hand.

Corner joints

The sides of the cajon were put together using miter joints cut on the table saw and biscuits for alignment. This was the first time we had ever used the Porter Cable biscuit joiner on a miter joint. It worked very well. The miter joints were considerably easier to glue and clamp because of the biscuits.

Sanding!

Greg carefully sanded every surface using 220 grit paper and a Porter Cable Speedbloc sander on a no-slip sanding pad.

Making with the color!

Greg is a happy camper as he sees the results of dye applied ot the actual pieces. He did a number of test pieces beforehand to get the feel of how the dye would work with the wood. Birch is prone to blotching. The homestead dye product empasizes how well it works with difficult to stain woods. Its a very good product.

First glue up

The deep bass sound potential of the cajon is very dependent on glued joints that are air tight. Greg used plenty of glue and lots of clamps. This would have been a very challenging job without the biscuits.

Leveling the face for the drumskin

We used a large jointer plane to touch up the edges of the cajon body to be sure they were exactly flat and coplaner, so the drumskin and soundboard would glue down in an airtight manner.

Reinforcing the corners

We glued two three inch long plywood cleats in each corner to futher strengthen the cajon body. Not only must it be a solid instrument, but it also serves as a seat for the drummer when played in the traditional manner by sitting on it.

Clamps galore!

Greg did not spare any clamps when glueing on the drumskin and the opposing soundboard. He used plenty of glue and clamped every inch of every edge. This worked well. He used a long set cabinet glue from Titebond. Its like traditional Titebond except the allowable working time is three times as long.

Chamfering the corners

Greg used a small low angle block plane to carefully chamfer each corner edge of the cajon body.

Final finishing

Four coats of shellac with light sanding between coats and then three coats of nitrocellulous lacquer. The final coat was sanded using 800 grit lubed with mineral spirits, then polished with automotive compound. Final finish was hand rubbed paste wax. Be sure to wear an approved respirator. The lacquer is very toxic.